Lesson 5 · 15 min
WebMCP has already changed its name once and may change again before the origin trial ends. Whoever teaches or implements it needs to know, with dates, what the spec says, which browser runs it, and who is against it. In this lesson you read all of that straight from the primary sources with a script, and you learn to separate what is foundation from what is lab work.
Start the lesson
Goal: read from the source, with dates, where WebMCP stands: spec, origin trial, and each browser's position.
Click each step.
Exercises and assessment on the stable foundation. WebMCP as a lab, with a date and feature detection.
Four sources, one question each.
At the top of webmachinelearning.github.io/webmcp: the document type and the date. If the date has changed since your last read, reread what you use.
Look for the name of the surface. On 10/16/2026 it is document.modelContext; navigator.modelContext no longer appears.
The implementation-status.md in the spec repository says where there is an origin trial (Chrome 149, Edge 150) and what else exists (Brave Leo experimental, ChatGPT Desktop).
Chrome Status (entry 5117755740913664) gives the trial range and the stage.
Mozilla and WebKit publish positions in open issues: mozilla/standards-positions #1412 and WebKit/standards-positions #670. The "position:" label gives the position.
Everything that depends on a flag, origin trial, or explainer gets the "experimental on DD/MM/YYYY" stamp. WebMCP is preparation, not ranking: visibility in AI is a topic for the inemaSEO Program.
The switch from navigator.modelContext to document.modelContext was accepted on 05/19/2026 (PR #177). Courses written before that date teach the old API.
estado.sh downloads the spec and implementation-status.md, and reads the two position issues through the public GitHub API, with no login and no key. All you need is curl.
bash ~/projetos/formacao-webmcp-base-v72/kit/estado.sh; echo "saída: $?"
WebMCP on <dd/mm/yyyy> - spec: Draft Community Group Report of <date> (surface: <document.modelContext>) - Chrome: <origin trial / flag>; Edge: <origin trial> - Firefox: <position>; Safari: <position> - decision for my site: <wait | lab | register with feature detection and fallback>
spec WebMCP · versão de 2026-10-16 · not a W3C Standard document.modelContext: 16 menções · navigator.modelContext: 0 Chrome · An Origin Trial is live in Chrome 149 Edge · An Origin Trial is live in Edge 150 Firefox · mozilla/standards-positions #1412 · position: neutral Safari · WebKit/standards-positions #670 · position: oppose lido em 19/10/2026 saída: 0
The 10/16/2026 spec has 16 mentions of document.modelContext in its text and none of navigator.modelContext. There is an origin trial in Chrome 149 and Edge 150; Mozilla is neutral, WebKit is opposed.
Material from before May 2026 still shows navigator.modelContext, and September courses cite the 09/17/2026 draft. The date that counts is the one in the spec header on the day you read it. If the estado.sh shows a date other than 10/16/2026, the spec changed after this course: reread it before using any example from here.
Read the state today and note it with a date.
Run the "read the state" block. Compare each line with the output captured on 10/19/2026 and note what changed.
Done when: bash estado.sh prints a spec WebMCP · versão de line with a date, the Chrome ·, Edge ·, Firefox · and Safari · lines, and ends with saída: 0.
Fill in the "dated note" template with today's output and choose the decision for your site. It goes into the WebMCP section of the plan (lesson 8).
Done when: the note has a dd/mm/aaaa date, the spec date, the Firefox and Safari positions, and a written decision, with no <…> left over.
Question 1 of 4
What is the status of the WebMCP document on 10/16/2026?skill
Question 2 of 4
What is WebKit's (Safari's) position on WebMCP?skill
Question 3 of 4
In Chrome, how is WebMCP available to your site's visitors today?
Question 4 of 4
estado.sh shows a spec date other than 10/16/2026. What should you do?
Pick an answer. The explanation shows up after you try.